Paul and Silvanus and Timothy, to the assembly of the Thessalonians in God the Father and in the Lord Jesus Christ, grace to you and peace (1 Thessalonians 1:1).
Paul was only able to spend three Sabbaths with the saints in Thessalonica before the Jews incited the Gentiles to persecute the believers in the resurrection of Christ, seeking to kill Paul (Acts 17:2).
In his opening address to the saints in Thessalonica, Paul reveals an incredible truth that is often overlooked—the saints are also in God the Father. Our position in Christ pertains to the possessions and positions we have in salvation, freeing us from bondage to the sin nature and enabling us to live righteously. We live in light of this position now, as we await Christ’s call to meet Him in the air, so that He may present the Church to the Father.
Therefore, the position to which Paul is referring pertains to an eternal standing in which the saints of the Church will have a position in the Father. As for what this fully entails, we will have to wait until eternity to know, for in our present state we would not be able to comprehend it.